Draft gear



Patented Aug, 19 i224..

Marsa Stia a HARRY BARNARD, 0F CHICAGO, ILLINOIS, ASSIGNOR TO UNION DRAFT GEAR CO.,- A ORPORATXON OF ILLINOIS.

DRAFT GEAR.

Application filed February 10. 1922.

To aU ywhom t may concern:

Be it known that l, HARRY BARNARD, a citizen of the United States, and resident of Chicago, county of (look, and State of Illinois, have invented certain new and useful Improvements in Draft Gear, of which the following is a specification, and which are illustrated in the accompanying drawings, forming a part thereof. n

The invention lrelates to draft gear for railway cars, its object being to provide a simple form of friction draft gear which will develop great power and be smooth in its action.

ln the embodiment of the invent-ion illustrated in the drawings, there is shown in- Fig. 1 a detail plan view of the underframing of a car with the improved gear applied thereto, and shown in release position;

Fig. L, a sectional view of the gear taken on the line 2-2 of Fig. l;

Fig. 3, a horizontal section taken on the line 3MB of Fig. 2, but showing the gearfin compressed position under bu g Fig. 4f, a perspective of one of the friction plates used in the gear; and

F ig. 5, one of its friction wedge blocks.

There is represented at 10, 10, a pair of draft sills vof a railway car which may be of any preferred form of construction, at 11, 11, a pair of draft'lugs, and at 12, 12, a pair of batting lugs-attached to the sills. The butt of a coupler is shown at 13, and a conventional form of yoke for inclosing thedi'aft gear, and being attached to the coupler butt, is represented at 14, 14.

The improved draft gear comprises a box-like casing 15, the rear closed end of which is adapted to abut against the buiiing lugs 12, 12. A, front follower 16 is located forward of the` open end of the casing 15, and co-operates with the draft lugs 11, 11, and receives the impact, in buling, of the coupler butt 13. The length of the casing 15 is such as to provide for the necessary range of movements of the. two part-s referred to, and preferably to serve as a limiting stop to prevent over compression. A plate 17 is disposed on the median line of the casing 15, and is shown as cast integral with the follower 16, although any form of physical connection between these two parts will serve. The width of the plate is substantially that of the chaml'ier of the casing Serial No. 535.462.

4These friction plates are held against longitudinal movement by means of a key 20 setting through the side Walls of the casing 15 and passing through an elongated aper-A ture in the plate 17. The plates 17, 18, and 19 collectively divide the chamber of the casing 15 into two compartments, and within each of these compartments is housed friction developing wedge members and cushioning springs. The two sets'of these devices being identical in form, but one of them need be described in detail.

Each set of friction developing devices comprises a pair of wedge blocks 21, 22. Each of these blocks is provided with a flat face, the flat faces of the outer blocks vengaging the walls of the casing 15 and the flat faces of the inner blocks engaging the plates 18 and 19. The inner faces of the blocks 21 and 22 are inclined, as shown .at 24, 25, to form wedging surfaces, and each of the blocks is provided with an elongated aperture. 2G to accommodate the key 2O and allow relative' movement with reference thereto.

Interposed between the adjacent vwedging faces 24 of the blocks 21, 22, there is a` triangular block 27, and interposed between the faces 25 of these. blocks is a similar triangularblock 28. A helical spriner 29 reacts between the block 27 and the follower 16, and a similar spring 30 reacts between the block 2S and the end wall of the casing stresses the follower 1.6 isinved leaekvvarcln ly, compressing thevsprings 29 seated against it, which in turn urge backwardly the tr1- angular wedge-blocks 27, the advance of these blocks spreading apart the blocks 2l, 22, and forcing them into frictional engagement with the plates 18, 19, and the latter into frictional engagement with the plate 17.-

The blocks 21 and 22 are moved backwardly/as well as laterally, and consequently ride up upon the faces of the triangular block 28, with which they make'contact, and push these blocks backwardly against the resistance of the springs 30. When the backward movement of the follower 16 has been sufficient to bring the guide stem 3l into contact with the guide stem 32, the springs 29 are no further compressed but the blocks 27 are positively moved backwardly, causing a further compression ot' the springs 30. As shown, the noses of the triangularbloclrs 27, 28, are slotted to provide clearance for the key 20,

' The springs employed in the gear are of sufficient power to insure a wedging action by the relative approach of the triangular blocks 2T, 28, and friction is developed between the parts having a sliding engagement ink proportion to the extent, of movement of the follower 16.

When the pressure of the coupler butt on the follower A1.6 is relieved the various parts return to the position of rest under the inlluence of the springs 29, supplemented by the tendency of the wcdging elements to separate under the influence of lateral pressure to which they have been subjected. The pitch of the wedging faces is such as to provide for a gradual development of wedging ressure and to facilitate the release action.

pon the release the springs at opposite ends of the gear measurably counteract each other. The tendency of the forward springs is to violently return the follower 16 to normal position. This tendency-is not only resisted by the frictional engagement of the v various parts, but the too sudden release of this engagement is insured by the expansive action of the rearward springs.

Upon the application ot' draft'stresses the action of the gear is the saine as in buiing, except that the casing and its contained elements other than the Iplate 17 move fore wardly. p j

Various changesy of detail may be made within the scope of the-intention, as, for example, the rear end ol.' the casing, while shown as attachedto the body, need not necessarily be so.

l claim as my inventionl. In a draft gear, in gornbination, a cas ing having a closed cndVa friction plate inoyable on the longitudinal median plane of the casing, a pair et' plates frictionally engagcalile with the oppositey faces of the first-named plate, means for preventing relative longitudinal movement ot the pair of plates and the casing` and means including springs at each end of said casing for pressing the pair olt plates against the central plata 2. In a dral't gear, in combination, a casing, resilient means associated with said casing, a friction plate movable on the longitudinal median plane of the casing, pair of plates trictionally engagcabli': with the opposite faces el the iirst-nained plate, means for preventing relative longitinlinal movement of the pair ot plates and the casing, and wedge means operated by the initial rnoven'ient of said resilient means for pressing the pair ot' plates against the central plate ing, a follower therefor, a friction plate rigidly secured to said follower and movable on the longitudinal median plane of the easing, a pair ot' plates lrictionally engageable with the opposite faces oi the first-named plate, means for preventing relative longi tudinal movement of the pair of plates and the easing. means tor pressing the pair o plates against the central plate, and spring means for withdrawing the central plate after an advance movement,

'slin a draft gear, in combination, a casing having a closed end, a follower opposed to the open end of the easing, a longitudinally movable plate centrally disposed in. the casing and normally7 projecting beyond its open end, a pair ol plates flanking and friotionally engaging the rfirst-named plate and being anchored to the casing against longi# tudinal movement, two 'pairs of friction shoes one ol' each pair being seated against the side walls of the easing and the other against one ot' the pair of plates, the adja cent faces of each pair of shoes being wedgeshapcd, a wedge block interposed between opposed wedge faces of the shoes, and| springs reacting between the several wedge blocks and the end of the. casing and the follower, respectively.

5. In a draft gear, in combination, a easing having a closed end, a follower opposed to the open end ot the casing, alongitudi nally movable plate centrally disposed in the casing and norn'ially projecting beyond its open cud, a pair of `plates flanking and'frietionally engaging the first-named plate and being anchored to the casing against longitudinal movement, two pairs of friction shoes one of cach pair being seated against the side walls ot' the easing and the other against one of the pair of plates, the adjacent faces of each pair of shoes being wedgeshaped, a wedge block interposed between opposed wedge lfaces'of the shoes, springs reacting between the several wedge blocks and the end oi' the easing and the follower, respectively, andyspring guides carried by 3. ln a draft gear, in combination. a casthe follower and engageable with a pair of the wedge blocks upon the compression of the springs.

t5. In a draft gear, the combination of a casing having a closed. end, a friction plate moving in the longitudinal median plane of the casing, a pair of friction plates engaged with the opposite faces of the first named plate and extending substantially from one end of said casing to the other, means for preventing relative longitudinal movement of the pair of plates and the casing and 'spring pressed wedged means for pressin y the pair of plates against the first name plate.

7. In a draft gear, the combination of a casing, a follower. a plate centrally disposed in the casing and secured to the follower, friction plates fianking and frictionall engaged with the first named plate an anchored against longitudinal movement in the easing, wedge means between the friction plates and the casing, springs between the follower and tlie wedge means and means at the end of said casing opposite said follower for yieldingly resisting relative movement of said wedge means in one direction relatively to said casing.

8. Ina draft gear, the combination of a casing having a closed end, a follower opposed t0 the open end of the casing, a plate centrally disposed in the casing and secured to the follower, friction plates flanking and frctionally engaged with the first named plate and anchored against longitudinal movement in the casing, relatively movable wedge elements between each friction plate and the casing and springs between said Wedge elements and the closed end of the easing, and between said elements and the follower.

9. In a draft gear, the combination with a casing, a follower, a plate carried bylsaid follower and operating within said casing; a pair of friction plates engaging opposite faces of they' first named plate, springs, means engaged by said springs for forcing the pair of plates Yagainst the rst named plate, and means carried by the follower' HARRY BARNARD. 

